In-situ semiconductor processing chamber temperature apparatus

ABSTRACT

In one implementation, a showerhead assembly is provided. The showerhead assembly comprises a first electrode having a plurality of openings therethrough and a gas distribution faceplate attached to a first lower major surface of the electrode. The gas distribution plate includes a plurality of through-holes for delivering process gases to a processing chamber. The gas distribution plate is divided into a plurality of temperature-control regions. The showerhead assembly further comprises a chill plate positioned above the electrode for providing temperature control and a plurality of heat control devices to manage heat transfer within the showerhead assembly. The heat control device comprises a thermoelectric module and a heat pipe assembly coupled with the thermoelectric module. Each of the plurality of heat control devices is associated with a temperature control region and provides independent temperature control to its associated temperature control region.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims benefit of U.S. Provisional Patent ApplicationSer. No. 62/521,879, filed Jun. 19, 2017, which is incorporated hereinby reference in its entirety.

BACKGROUND Field

Implementations described herein generally relate to semiconductorprocessing, and more specifically, to apparatuses and methods forin-situ temperature measurement for the inside of a semiconductorprocessing chamber.

Description of the Related Art

Semiconductor devices are commonly fabricated by a series of processesin which layers are deposited on a surface of a substrate and thedeposited material is etched into desired patterns. As semiconductordevice geometries decrease, precise process control during theseprocesses becomes more and more important.

Temperature control is particularly important to achieve repeatablesemiconductor manufacture with improved yield and high throughput inchambers, such as etch chambers, for semiconductor processing. Precisemanufacturing techniques have small process windows, and even slightvariations out of acceptable process control tolerances can lead tocatastrophic amounts of production defects. For example, when thetemperature of the showerhead assembly, the chuck surface, or chambersidewalls is too low, there is an increased risk of polymer depositionon these cold spots, which can undesirably alter etch sidewall profiles.When, for example, the temperature of the showerhead assembly is toohigh, there is an increased risk of films on the faceplate of theshowerhead assembly cracking and flaking off, which may cause defects onthe substrate. Furthermore, temperature drift of chamber processingsurfaces including the gas distribution assembly, chamber sidewalls andchuck surface will also undesirably cause processing results to varyfrom substrate to substrate.

Therefore, there is a need for an improved method and apparatus formonitoring the temperature of chamber surfaces and internal chambercomponents in a semiconductor-processing chamber.

SUMMARY

Implementations described herein generally relate to semiconductorprocessing, and more specifically, to apparatuses and methods forin-situ temperature measurement for the inside of a semiconductorprocessing chamber. In one implementation, a showerhead assembly isprovided. The showerhead assembly comprises a first electrode having aplurality of openings therethrough and a gas distribution faceplateattached to a first lower major surface of the electrode. The gasdistribution plate includes a plurality of through-holes for deliveringprocess gases to a processing chamber. The gas distribution plate isdivided into a plurality of temperature-control regions. The showerheadassembly further comprises a chill plate positioned above the electrodefor providing temperature control and a plurality of heat controldevices to manage heat transfer within the showerhead assembly. The heatcontrol device comprises a thermoelectric module and a heat pipeassembly coupled with the thermoelectric module. Each of the pluralityof heat control devices is associated with a temperature control regionand provides independent temperature control to its associatedtemperature control region.

In another implementation, a temperature-sensing disc is provided. Thetemperature-sensing disc comprises a disc-shaped body. The disc-shapedbody has a diameter of 300 millimeters, a front surface, and a backsurface opposing the front surface. The temperature-sensing disccomprises further comprises one or more cameras positioned on at leastone of the front surface and the back surface, wherein the one or morecameras are configured to perform IR-based imaging.

In yet another implementation, a processing chamber is provided. Theprocessing chamber comprises a chamber body having a top wall, sidewall,and bottom wall defining a processing volume. The processing chamberfurther comprises a substrate support assembly positioned in theprocessing volume and a showerhead assembly positioned opposite thesubstrate support. The showerhead assembly comprises a first electrodehaving a plurality of openings therethrough, a gas distributionfaceplate attached to a first lower major surface of the electrode. Thegas distribution plate includes a plurality of through-holes fordelivering process gases to a processing chamber. The gas distributionplate is divided into a plurality of temperature-control regions. Theshowerhead assembly further comprises a chill plate positioned above themetal electrode for providing temperature control and a plurality ofheat control devices to manage heat transfer within the showerheadassembly. The plurality of heat control devices each comprise athermoelectric module and a heat pipe assembly coupled with thethermoelectric module, wherein each of the plurality of heat controldevices is associated with a temperature control region and providesindependent temperature control to its associated temperature controlregion.

In yet another implementation, a substrate support assembly is provided.The substrate support assembly comprises an upper surface for supportinga substrate, wherein the upper surface is divided into a plurality oftemperature-control regions and a plurality of heat control devices tomanage heat transfer within the substrate support assembly. Each heatcontrol device comprises a thermoelectric module and a heat pipeassembly coupled with the thermoelectric module. Each of the pluralityof heat control devices is associated with a temperature control regionand provides independent temperature control to its associatedtemperature control region.

In yet another implementation, a method is provided. The methodcomprises delivering a temperature-sensing disc into a processing regionof a processing chamber without breaking vacuum. The temperature-sensingdisc includes one or more cameras configured to perform IR-basedimaging. The method further comprises measuring a temperature of atleast one region of at least one chamber surface in the processingregion of the processing chamber by imaging the at least one surfaceusing the temperature-sensing disc. The method further comprisescomparing the measured temperature to a desired temperature to determinea temperature difference. The method further comprises adjusting atemperature of the at least one chamber surface to compensate for thetemperature difference.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the above-recited features of the presentdisclosure can be understood in detail, a more particular description ofthe implementations, briefly summarized above, may be had by referenceto implementations, some of which are illustrated in the appendeddrawings. It is to be noted, however, that the appended drawingsillustrate only typical implementations of this disclosure and aretherefore not to be considered limiting of its scope, for the disclosuremay admit to other equally effective implementations.

FIG. 1 is a plan view of an example of a processing system in accordancewith one or more implementations of the present disclosure;

FIG. 2 is a cross-sectional view of an example of a processing chamberin accordance with one or more implementations of the presentdisclosure;

FIG. 3A is a top view of one example of a temperature-sensing disc inaccordance with one or more implementations of the present disclosure;

FIG. 3B is a cross-sectional view of the temperature-sensing disc takenalong line 3B-3B of FIG. 3A in accordance with one or moreimplementations of the present disclosure;

FIG. 4 is a cross-sectional view of a showerhead assembly in accordancewith one or more implementations of the present disclosure;

FIG. 5 is a cross-sectional view of a thermoelectric module that may beused with a heat control device in accordance with one or moreimplementations of the present disclosure;

FIG. 6 is a cross-sectional view of a heat pipe assembly that may beused with a heat control device in accordance with one or moreimplementations of the present disclosure;

FIGS. 7A-7D depict schematic views of various chamber surfaces that maybe used with a heat control device in accordance with one or moreimplementations of the present disclosure; and

FIG. 8 is a process flow diagram of one implementation of a method forin-situ temperature control in accordance with one or moreimplementations of the present disclosure.

To facilitate understanding, identical reference numerals have beenused, where possible, to designate identical elements that are common tothe figures. It is contemplated that elements and features of oneimplementation may be beneficially incorporated in other implementationswithout further recitation.

DETAILED DESCRIPTION

The following disclosure describes techniques and apparatus fortemperature control and substrate processing chambers. Certain detailsare set forth in the following description and in FIGS. 1-8 to provide athorough understanding of various implementations of the disclosure.Other details describing well-known structures and systems oftenassociated with etch processes, deposition processes, and temperaturecontrol, are not set forth in the following disclosure to avoidunnecessarily obscuring the description of the various implementations.

Many of the details, dimensions, angles and other features shown in theFigures are merely illustrative of particular implementations.Accordingly, other implementations can have other details, components,dimensions, angles and features without departing from the spirit orscope of the present disclosure. In addition, further implementations ofthe disclosure can be practiced without several of the details describedbelow.

Implementations described herein will be described below in reference toa temperature control process that can be carried out using any suitablethin film deposition or etch system. Examples of suitable systemsinclude the CENTURA® systems, PRECISION 5000® systems, PRODUCER®systems, PRODUCER® GT™ systems, PRODUCER® XP Precision™ systems,PRODUCER® SE™ systems, Sym3® processing chamber, and Mesa™ processingchamber, all of which are commercially available from Applied Materials,Inc., of Santa Clara, Calif. Other tools capable of performing in-situtemperature control processes may also be adapted to benefit from theimplementations described herein. In addition, any system enabling thein-situ temperature control processes described herein can be used toadvantage. The apparatus description described herein is illustrativeand should not be construed or interpreted as limiting the scope of theimplementations described herein.

Some implementations of the present disclosure generally relate tosemiconductor plasma etch chamber technology and hardware controlsystems for addressing the issue of non-uniformity of heating or coolingshowerhead chamber surfaces (e.g., top electrode, bottom electrode, andchamber sidewall) in the etch process chamber.

As technology nodes advance and feature sizes are reduced, precisecontrol of RF, gas flow and thermal control will help to achieve onwafer uniformity with device performance and improved yield forsemiconductor processing with lower cost per wafer. Based on thechemistry used for etching and process application requirements, uniformsteady heating or cooling across chamber surfaces (e.g., showerheadassembly, electrostatic chuck, and chamber walls) is paramount toachieve repeatable process results. Since plasma etching creates heat onthe exposed surface of the showerhead assembly, controlling thetemperature of the showerhead assembly and other chamber surfaces iscritical to avoid hot or cold spots on the surface. These hot and coldspots can lead to polymer adhesion on the cold spots, which cause sloweretch rates and profile control issues. This problem is exacerbated whenetching higher aspect ratio features and other 1×nm node criticalapplications.

Semiconductor plasma processing hardware typically includes a highvacuum chamber with a pumping system. Often, top source/electrode withshowerhead and gas distribution is used depending on the application andfilm being processed and silicon wafers are etched while beingelectrostatically clamped to an electrostatic chuck inside the vacuumchamber during plasma processing. To maintain process uniformity andcritical dimension (“CD”) variation within a certain range, electrical(AC/DC/RF) control, gas flow control and thermal uniformity arecritical. Some implementations of the present disclosure provide methodsand apparatus for maintaining zone enabled heating and cooling of ashowerhead assembly and other chamber surfaces, which include a closedloop control system used for in-situ tuning temperature.

In some implementations of the present disclosure, an IR camera embeddedon a wafer-sized disc (vacuum compatible material) is used to monitorthe temperature of one or more surfaces within the processing chamber.In some implementations, cameras (e.g., nano-cameras), which areembedded on at least one of the top surface and the bottom surface ofthe disc, enable IR-based imaging of the top electrode (e.g., theshowerhead assembly) and the bottom electrode (e.g., the electrostaticchuck), and the chamber wall without venting the process chamber.Further, the disc can move from a stored location in a FOUP to atransfer chamber and finally to the process chamber without venting theprocess chamber. In addition, an existing platform robot may be used totransfer the disc inside the process chamber. When inside the processchamber, existing wafer lift pins may be used to position the disc toimage both the top and bottom electrodes. The image data can betransferred wirelessly to an external device and control system tocreate a temperature profile map of the electrode and chamber surfaces.Depending on the location of hot or cold spots as indicated by thetemperature map, the temperature of the electrode and chamber surfacescan be tuned (increased or decreased) at the pixel level to create amore uniform temperature profile.

In some implementations of the present disclosure, an improvedshowerhead assembly design is provided. Traditional showerhead assemblydesigns include a standard chill plate where the entire area of thechill plate is either heated or cooled. In some implementations of thepresent disclosure, a showerhead assembly in which temperature can becontrolled via multiple zones or pixels is provided. Typical showerheaddesigns include a gas distribution plate, which is typically ceramic,bonded to an aluminum base to increase life and yield. In someimplementations of the present disclosure, heat pipes are used as partof a heat-transfer device that combines the principles of both thermalconductivity and phase transition to efficiently manage the transfer ofheat between two solid interfaces (e.g., the top and bottom aluminumplates). Some implementations of the present disclosure also include ashowerhead assembly with a top and bottom aluminum-base connected with aseries of heat pipes. The heat pipes may be positioned in pre-definedpattern of pixels.

In some implementations of the present disclosure, each pixel element orregion of the showerhead assembly is also connected to a thermoelectricelement (e.g., p-type and n-type elements). Each thermoelectric elementis coupled with a heat pipe to form a heat control device. Each heatcontrol device is coupled with a pixel or region to independentlycontrol the temperature of that pixel or region. The thermoelectricelements are configured to be electrically connected in series butthermally connected in parallel to ensure maximum power generationoutput, which is reversible so that both module types can act as acooler or a generator; if a voltage is applied to a module, it will pumpheat. Some implementations of the present disclosure also include astandard chill plate, which is used as a heat exchanger to globally heatand cool the temperature of the showerhead assembly rapidly. In someimplementations, the temperature tuning of the showerhead assembly toremove hot or cold spots is achieved using the IR-based imaging data andwireless data exchange with external control system and pixel controlfor temperature tuning.

FIG. 1 is a plan view of an example of a processing system 100 inaccordance with one or more implementations of the present disclosure.FIG. 1 depicts the possible movement of a temperature-sensing disc 300through the processing system 100. The processing system 100 generallyincludes a factory interface 105, a side storage pod 103 for storing thetemperature-sensing disc 300, a transfer chamber 112, an atmosphericholding station 109, and a plurality of twin processing chambers 108a-108 b, 108 c-108 d and 108 e-108 f. The factory interface 105 isoperating at atmospheric pressure for storing and holding substrates.The factory interface 105 includes at least one atmospheric robot 104,such as a dual-blade atmospheric robot, and is configured to receive oneor more cassettes of substrates.

On a first side of the factory interface 105, one or more load ports maybe provided. In one implementation, three load ports are provided. Forclarity, only two load ports 111, 113 are depicted in the implementationof FIG. 1. The load port 111, 113 is adapted to receive from a frontopening unified pod (“FOUP”) 102 a substrate (e.g., 300 mm diameterwafers) which is to be processed. The FOUP(s) 102 has one or moresubstrate carriers configured to temporarily and portably store thesubstrates. A load lock chamber 106 is coupled to a second side(opposing to the first side) of the factory interface 105. The load lockchamber 106 is coupled to the transfer chamber 112 in which theplurality of twin processing chambers 108 a-108 b, 108 c-108 d and 108e-108 f are located.

The substrate is transferred by the atmospheric robot 104 from theFOUP(s) 102 to the load lock chamber 106. A second robotic arm 110 isdisposed in the transfer chamber 112 coupled to the load lock chamber106 to transport the substrates from the load lock chamber 106 toprocessing chambers 108 a-108 f coupled to the transfer chamber 112. Thefactory interface 105 therefore provides a transition between theatmospheric environment of the factory interface and the vacuumenvironment of the tool or processing chambers.

The processing chambers 108 a-108 f may be any type of processingchambers, for example, chemical vapor deposition (CVD) chambers, atomiclayer deposition (ALD) chambers, physical vapor deposition (PVD)chambers, ion metal implant (IMP) chambers, plasma etching chambers,annealing chambers, other furnace chambers, etc. In one implementation,the processing chambers 108 a-108 f are configured for depositing,annealing, curing and/or etching a film on a substrate. In oneconfiguration, three pairs of the processing chambers (e.g., 108 a-108b, 108 c-108 d and 108 e-108 f) may be used to deposit the film on thesubstrate. If desired, any of these processing chambers 108 a-108 b, 108c-108 d and 108 e-108 f, or one or more additional processing chambersmay be coupled to the transfer chamber 112 and arranged to perform otherconventional semiconductor device fabrication process such as oxidation,film deposition, etching, heating, degassing, ashing, ion implanting,metrology, etc. upon application.

The side storage pod 103 may include a chamber body 103B for holding thetemperature-sensing disc 300 and a slit valve 103A. The slit valve 103Ais used to seal-off an internal region of the chamber body 103B afterthe temperature-sensing disc 300 has been positioned therein by theatmospheric robot 104.

The temperature-sensing disc 300 is transferred by the atmospheric robot104 from the side storage pod 103 to the load lock chamber 106. A secondrobotic arm 110 is disposed in the transfer chamber 112 coupled to theload lock chamber 106 to transport the temperature-sensing disc 300 fromthe load lock chamber 106 to processing chambers 108 a-108 f wheretemperature monitoring is performed.

In some implementations, the temperature-sensing disc 300 is positionedin the FOUP(s) 102. The temperature-sensing disc 300 is transferred bythe atmospheric robot 104 from the FOUP(s) 102 to the load lock chamber106. A second robotic arm 110 is disposed in the transfer chamber 112coupled to the load lock chamber 106 to transport thetemperature-sensing disc 300 from the load lock chamber 106 toprocessing chambers 108 a-108 f coupled to the transfer chamber 112.

FIG. 2 is a cross-sectional view of an example of processing chamber 200having the temperature-sensing disc 300 disposed therein in accordancewith one or more implementations of the present disclosure. Theprocessing chamber 200 may be any of the processing chambers 108 a-f ofprocessing system 100. The processing chamber 200 is coupled with a gaspanel 210 and a control system 220. The processing chamber 200 generallyincludes a chamber body 230 having a top wall 232, a sidewall 234 and abottom wall 236. The top wall 232, the sidewall 234 and the bottom wall236 define a processing volume 238. A substrate support assembly 240 isprovided in the processing volume 238 of the processing chamber 200. Thesubstrate support assembly 240 generally includes an electrostatic chuck242 supported by a stem 244. The electrostatic chuck 242 may befabricated from aluminum, ceramic, and other suitable materials. Theelectrostatic chuck 242 may be moved in a vertical direction inside theprocessing chamber 200 using a displacement mechanism (not shown).

The electrostatic chuck 242 has an upper surface 246 for supporting asubstrate. Lift pins 243 are moveably disposed through the substratesupport assembly 240 and are adapted to space the substrate (if present)or the temperature-sensing disc 300 from the upper surface 246. Thetemperature-sensing disc 300 is positioned a suitable distance from thesurface(s) to be monitored (e.g., any one of the upper surface 246 ofthe electrostatic chuck 242, the surfaces of the showerhead assembly260, the surfaces of the sidewall, the surfaces of the top wall 232, andthe surfaces of the bottom wall.) In one implementation, as depicted inFIG. 2, the temperature-sensing disc 300 is positioned in the processingvolume 238 using the lift pins 243 such that the temperature-sensingdisc 300 can monitor multiple surfaces.

The electrostatic chuck 242 includes a chucking electrode 248, which maybe a mesh of a conductive material. The chucking electrode 248 may beembedded in the electrostatic chuck 242. The chucking electrode 248 iscoupled with a power source 274 that, when energized, electrostaticallyclamps a substrate to the upper surface 246 of the electrostatic chuck242. The power source 274 may be coupled with the chucking electrode 248via a matching network 276.

A showerhead assembly 260 having a plurality of apertures 262 isdisposed on the top of the processing chamber 200 above theelectrostatic chuck 242. The apertures 262 of the showerhead assembly260 are utilized to introduce process gases into the processing chamber200. The apertures 262 may have different sizes, number, distributions,shape, design, and diameters to facilitate the flow of the variousprocess gases for different process requirements. The showerheadassembly 260 is connected to the gas panel 210 that allows various gasesto supply to the processing volume 238 during processing. A plasma isformed from the process gas mixture exiting the showerhead assembly 260to enhance thermal decomposition of the process gases resulting inetching or deposition of material on a surface of a substrate not shown.

The showerhead assembly 260 and the electrostatic chuck 242 may form apair of spaced apart electrodes in the processing volume 238. One ormore RF power source(s) 270 provide a bias potential through an optionalmatching network 272 to the showerhead assembly 260 to facilitategeneration of plasma between the showerhead assembly 260 and theelectrostatic chuck 242. Alternatively, the RF power source 270 andmatching network 272 may be coupled to the showerhead assembly 260,electrostatic chuck 242, or coupled to both the showerhead assembly 260and the electrostatic chuck 242, or coupled to an antenna (not shown)disposed exterior to the processing chamber 200.

A vacuum pump 250 is coupled to a port formed in the bottom wall 236 ofthe processing chamber 200. The vacuum pump 250 is used to maintain adesired gas pressure in the processing chamber 200. The vacuum pump 250also evacuates post-processing gases and by-products of the process fromthe processing chamber 200.

The processing chamber 200 may further include additional equipment forcontrolling the chamber pressure, for example, valves (e.g., throttlevalves and isolation valves) positioned between the chamber body 230 andthe vacuum pump 250 to control the chamber pressure.

The control system 220 includes a central processing unit (CPU) 222, amemory 226, and a support circuit 224 utilized to control the processsequence and regulate the gas flows from the gas panel 210. The CPU 222may be of any form of a general-purpose computer processor that may beused in an industrial setting. The software routines can be stored inthe memory 226, such as random access memory, read only memory, floppy,or hard disk drive, or other form of digital storage. The supportcircuit 224 is conventionally coupled to the CPU 222 and may includecache, clock circuits, input/output systems, power supplies, and thelike. Bi-directional communications between the control system 220 andthe various components of the processing chamber 200 are handled throughnumerous signal cables collectively referred to as signal buses 228,some of which are illustrated in FIG. 2.

FIG. 3A is a top view of one example of the temperature-sensing disc 300in accordance with one or more implementations of the presentdisclosure. FIG. 3B is a cross-sectional view of the temperature-sensingdisc 300 taken along line 3B-3B of FIG. 3A in accordance with one ormore implementations of the present disclosure. In some implementations,the temperature-sensing disc 300 is an IR-based temperature-sensingdisc. The temperature-sensing disc 300 is typically sized similarly tothe wafers processed by the processing chamber. For example, in someimplementations where the processing system is configured to process 300mm sized wafers, the temperature-sensing disc 300 is sized similarly toa 300 mm wafer sized disc. In some implementations, where the processingsystem is configured to process 200 mm sized wafers, thetemperature-sensing disc 300 is sized similarly to a 200 mm wafer sizeddisc. Sizing the temperature-sensing disc 300 similarly to the wafersprocess by the processing chamber allows the temperature-sensing disc300 to move from its stored location (e.g., either the FOUP or the sidestorage pod) to the transfer chamber and finally to the processingchamber without venting the processing chamber. The existing platformrobots can be used to transfer the temperature-sensing disc 300 into theprocessing chamber. The temperature-sensing disc 300 may be positionedin the processing chamber using existing lift pins. Although describedas a disc, the temperature-sensing disc 300 may have other shapesdepending on the process chamber to be monitored.

The temperature-sensing disc 300 may comprises any vacuum compatiblematerial. Suitable materials include dielectric materials andsilicon-containing materials. In one implementation, thetemperature-sensing disc 300 is composed of a silicon-containingmaterial. In some implementations, the temperature-sensing disc 300 iscomposed of a dielectric material.

The temperature-sensing disc 300 has one or more cameras 310 a-310 i(collectively “310”) positioned thereon. The one or more cameras 310 aretypically configured to perform IR-based imaging of the surfaces withinthe processing chamber. In one implementation, the cameras 310 areconfigured to perform infrared imaging of the chamber surfaces and totransmit the infrared images wirelessly from the inside of theprocessing chamber. The cameras 310 may be attached to thetemperature-sensing disc 300 using any suitable attachment methods. Insome implementations, the cameras 310 are glued to the surfaces of thetemperature-sensing disc 300. In some implementations, the cameras 310are either partially embedded or fully embedded into the body of thetemperature-sensing disc 300. In some implementations, the one or morecameras are nano-cameras.

In some implementations, cameras 310 are positioned on both the frontsurface 320 and the back surface 330 of the temperature-sensing disc300. Positioning cameras 310 on both the front surface 320 and the backsurface 330 of the temperature-sensing disc 300 allows opposing chambersurfaces to be simultaneously imaged. For example, referring to FIG. 2,the cameras 310 on the front surface 320 can image the surface of theshowerhead assembly 260 while the cameras 310 on the back surface 330can image the upper surface 246 of the electrostatic chuck 242. In someimplementations, cameras 310 are positioned on only the front surface320 or the back surface 330 of the temperature-sensing disc 300. In someimplementations, nine or more cameras are positioned on the frontsurface of the disc-shaped body. In some implementations, nine or morecameras are positioned on the back surface of the disc-shaped body. Itshould also be understood that any number of cameras may be useddepending upon, for example, the number of surfaces to be monitored andthe total surface area to be monitored.

FIG. 4 is a cross-sectional view of a showerhead assembly 400 inaccordance with one or more implementations of the present disclosure.In some implementations, the showerhead assembly 400 may be used inplace of showerhead assembly 260 in processing chamber 200. Theshowerhead assembly 400 incorporates one or more heat control devices460 a-460 e (collectively 460) to manage heat transfer within theshowerhead assembly 400. Each heat control device 460 includes athermoelectric module 464 a-464 e (collectively 464) and a heat pipeassembly 466 a-466 e (collectively 466). In some implementations, eachheat control device 460 is associated with a pixel or region as will bediscussed in FIGS. 7A-7D. Each heat control device 460 providesindependent temperature control to its associated pixel or region.

The showerhead assembly 400 includes a chill plate (lid) 420, a topplate 430, a bottom plate 440, and a gas distribution faceplate 450. Thechill plate 420 is positioned on the top plate 430. The chill plate 420provides temperature control off the showerhead assembly 400. A recess422 is defined between the chill plate 420 and the top plate 430.

The top plate 430 includes a plurality of through-holes 432. In oneimplementation, each of the plurality of through-holes 432 accommodatesa heat pipe assembly 466 of the heat control device 460. In someimplementations, the top plate 430 has a second plurality ofthrough-holes (not shown in this view) for delivering process gases intoa processing chamber. The top plate 430 can be made of aluminum,ceramic, Si—Si carbide, or graphite converted to silicon carbide, forexample and not by way of limitation. In one implementation, the topplate 430 is a metal plate. In one implementation, the top plate 430 ismade of aluminum. In some implementations, the top plate 430 is made ofanodized aluminum.

The bottom plate 440 includes a plurality of holes 442. In oneimplementation, each of the plurality of holes 442 accommodates aportion of the heat pipe assembly 466 of the heat control device 460. Insome implementations, the bottom plate 440 has a second plurality ofthrough-holes (not shown in this view) for delivering process gases intothe processing chamber. The bottom plate 440 can be made of aluminum,ceramic, Si—Si carbide, or graphite converted to silicon carbide, forexample and not by way of limitation. In one implementation, the bottomplate 440 is a metal plate. In one implementation, the bottom plate 440is made of aluminum. In some implementations, the bottom plate 440 ismade of anodized aluminum.

The gas distribution faceplate 450 includes a plurality of through-holes(not shown) for delivering processing gases into the interior of thesemiconductor-processing chamber. The through-holes in the gasdistribution faceplate 450 can be, for example and without limitation,round or crescent-shaped.

The gas distribution faceplate 450 can be made of silicon carbide,yttrium oxide, anodized aluminum, ceramic, quartz, or silicon, forexample and not by way of limitation. In one implementation, the gasdistribution faceplate 450 is made of silicon carbide. The gasdistribution faceplate 450 may be bonded to a first, lower major surface444 of the bottom plate 440 by a bonding layer 446. In someimplementations, the bonding layer 446 is accomplished using asilicone-based adhesive with different types of fillers tailored forenhancing thermal conductivity. Bonding of gas distribution faceplate450 to the bottom plate 440 can be accomplished using other materialsand/or methods known in the art. However, bonding of the gasdistribution faceplate 450 to the bottom plate 440 should be performedusing a bonding material, which has enough compliance to preventdelamination due to thermal mismatch between the gas distributionfaceplate 450 and the bottom plate 440. Although a bonding layer isshown, it should also be understood that the gas distribution faceplate450 may be attached to the showerhead assembly using other attachmentmethods known in the art.

The showerhead assembly 400 further includes the plurality of heatcontrol devices 460 a-460 e (collectively 460). Each heat control device460 includes a thermoelectric module 464 a-464 e (collectively 464)coupled with a heat pipe assembly 466 a-466 e (collectively 466). Eachheat control device 460 is associated with a pixel or region defined onthe gas distribution faceplate 450. Each heat control device 460combines the principles of both thermal conductivity and phasetransition to efficiently manage the transfer of heat between the topplate 430 and the bottom plate 440 and the chill plate 420. Each heatcontrol device 460 is associated with a pixel or region as will bedescribed in reference to FIGS. 7A-7D.

FIG. 5 is a cross-sectional view of a thermoelectric module that may beused with a showerhead assembly in accordance with one or moreimplementations of the present disclosure. The thermoelectric module maybe thermoelectric module 464 and the showerhead assembly may beshowerhead assembly 400. In general, the thermoelectric module 464 iscomposed of an n-type thermoelectric material 510, a p-typethermoelectric material 520, conductive metal layers 530 a and 530 b, atop substrate 540 a and a bottom substrate 540 b. In someimplementations, a first insulating layer 550 a is positioned betweenconductive metal layer 530 a and top substrate 540 a. In someimplementations, a second insulating layer 550 b is positioned betweenconductive metal layer 530 b and bottom substrate 540 b.

The n-type thermoelectric material 510 and the p-type thermoelectricmaterial 520 are lump-shaped, and both of the top substrate 540 a andthe bottom substrate 540 b possess high thermal conductivity. In someimplementations, the n-type thermoelectric material 510 and the p-typethermoelectric material 520 are made of a semiconductor or a semi-metalelement or compound possessing a high ZT value, such as bismuthtelluride ((BiSb)₂ (TeSe)₃) series, bismuth telluride (Bi₂Te₃), leadtelluride (PbTe) and tin telluride (PbSnTe) series that are doped withantimony and selenium, or compound series such as silicon (Si) andsilicon germanium (SiGe) series, half-Heusler dielectric alloy series (astrong magnetic non-iron alloy), silicide, or tungsten diselenide (WSe₂)series. Moreover, the thermoelectric elements can be formed by way ofsputtering, thermal evaporation, arc ion plating, chemical vaporevaporation, electroplating and chemical plating. However, in practicalapplication, the choice of materials and the ways of formation aredetermined according to the actual needs and practical conditions, andthe disclosure does not have specific restrictions.

The n-type thermoelectric material 510 and the p-type thermoelectricmaterial 520 are configured to be electrically connected in series butthermally connected in parallel to ensure maximum power generationoutput. The elements are then sandwiched between two ceramic plates, oneside covers the hot joins and the other side covers the cold joins. Theeffect is reversible so that both module types can act as a cooler or agenerator. If a voltage is applied to a module, it will pump heat, butif a temperature difference is applied across a module, a voltage willbe produced.

In some implementations, the top substrate 540 a and the bottomsubstrate 540 b also possess insulating properties. The functions of thethermoelectric module are mainly determined by the properties of thethermoelectric materials 510 and 520. As indicated in FIG. 5, the n-typethermoelectric material 510 and the p-type thermoelectric material 520are normally vertically type, and are connected in series via theconductive metal layers 530 a and 530 b.

In some implementations, the top and bottom substrates 540 a and 540 bwith electrical insulation and high thermal conductivity, for example,are made of ceramic material with high thermal conductivity realized bysuch as aluminum oxide, aluminum nitride and silicon carbide, or asilicon or metal substrate whose surface is covered with an insulatingdielectric layer. However, the disclosure does not have specificrestrictions regarding the choice of materials in practical application.In some implementations, the top substrate 540 a or heat sink platefunctions as a heat sink, which releases heat into, for example, thechill plate 420. In some implementations, the top substrate 540 a ispositioned adjacent to the chill plate 420. In some implementations, thebottom substrate 540 b functions as a cooling plate that absorbs heatfrom, for example, from the top plate 430 and/or the bottom plate 440.In some implementations, the bottom substrate 540 b is positionedadjacent to the top plate 430 and/or the bottom plate 440.

In the application of the thermoelectric cooling module, the inputteddirect current flows in the n-type thermoelectric material 510 and thep-type thermoelectric materials 520 in a direction (vertically flow)parallel to that of thermal flow (vertically transferring) of theconversion device, and the thermoelectric cooling module generatestemperature difference, and absorbs and dissipates the heat at thebottom and the top, respectively. Take power generation by way oftemperature difference for example. The directions of the thermoelectricmodule temperature difference and thermal flow are still parallel to theflow direction of the current generated in the thermoelectric materials.

FIG. 6 is a cross-sectional view of a heat pipe assembly that may beused with a showerhead assembly in accordance with one or moreimplementations of the present disclosure. The heat pipe assembly may beheat pipe assembly 466 and the showerhead assembly may be showerheadassembly 400. The heat pipe assembly 466 forms a portion of the heatcontrol device 460 of FIG. 4. As shown in FIG. 4, the heat controldevices 460 a-460 e are composed of a plurality of parallel andindependently operating heat pipes.

Each heat pipe assembly 466 includes a casing 606 enclosing a cavity608. The casing may be formed from a material with high thermalconductivity, such as copper or aluminum. The cavity 608 is vacuumed andfilled with a fraction of a percent by volume of a working fluid 612.The working fluid 612 may be water, ethanol, acetone, sodium, ormercury. The working fluid 612 may be chosen according to the operatingtemperature of the heat pipe assembly 466. Because the partial vacuumstate within the cavity, a portion of the working fluid 612 in thecavity 608 is in liquid phase and the remaining portion the workingfluid 612 is in gas phase.

The heat pipe assembly 466 may have a hot interface 602 configured to bein thermal contact with a target to be cooled at a first end and a coldinterface 604 configured to be in thermal contact with a heat sink ansecond end opposite to the hot interface 602. Optionally, a wickstructure 610 may be lined inside the casing 606 and surrounding thecavity 608. The wick structure 610 is configured to exert a capillarypressure on a liquid surface of the working fluid 612 at the coldinterface 604 and wick the working fluid 612 to the hot interface 602.

The heat pipe assembly 466 is a heat exchange device that combines theprinciple of both thermal conductivity and phase transition toefficiently manage the transfer of heat between the hot interface 602and the cold interface 604. At the hot interface 602 within a heat pipe,liquid of the working fluid 612 in contact with the casing 606 turnsinto vapor by absorbing heat from that heat source, that is in thermalcontact with the hot interface 602. The vapor condenses back into liquidat the cold interface 604, releasing the latent heat towards a heat sinkin thermal contact with the cold interface. The liquid then returns tothe hot interface 602 through either capillary action of the wickstructure 610, centrifugal force, or gravity action. The cycle repeats.

In one implementation, as depicted in FIG. 4, the hot interface 602 ofthe heat pipe assembly 466 is in thermal contact with at least one ofthe top plate 430 and the bottom plate 440, which are the surfaces to becooled, and the cold interface 604 is in thermal contact withthermoelectric module 464 and the chill plate 420, which functions as aheat sink.

FIGS. 7A-7D depict schematic views of various surfaces 700 a-700 d ofcomponents that are subject to temperature control using the heatcontrol devices according to one or more implementations of the presentdisclosure. Each surface 700 a-700 d is divided into a plurality ofsegments or pixels. Each segment is coupled with a heat control device,for example, heat control device 460, allowing for segmented temperaturecontrol of each temperature-control region of each surface 700 a-700 d.

The surfaces 700 a-700 d may be the surface of a gas distribution plate,an electrostatic chuck (e.g., the wafer support surface), or chamberwall. In one implementation, the surfaces 700 a-700 d represent variousdesigns for the surface of a gas distribution faceplate, for example,the surface of gas distribution faceplate 450 as depicted in FIG. 4. Inanother implementation, the surfaces 700 a-700 d represent variousdesigns for the wafer support surface of a chuck, for example,electrostatic chuck 242 as depicted in FIG. 2. In anotherimplementation, the surfaces 700 a-700 d represent various designs forthe surfaces of the chamber walls, for example, any of top wall 232, thesidewall 234, and the bottom wall 236 as depicted in FIG. 2.

FIG. 7A depicts a schematic view of one implementation of a surface 700a that may be subject to temperature control using the heat controldevices according to one or more implementations of the presentdisclosure. The surface 700 a includes a plurality of concentric regionsincluding a center region 702, a middle-inner region 704, a middleregion 706, a middle-outer region 708, and an outer region 710. Eachregion is divided into a plurality of segments or pixels that are eachsubject to independent heat control using the heat control devicesdescribed herein. The surface 700 a includes forty-eight segments.

FIG. 7B depicts a schematic view of another implementation of a surface700 b that may be subject to temperature control using the heat controldevices according to one or more implementations of the presentdisclosure. Similar to surface 700 a, surface 700 b includes a pluralityof concentric regions. The surface 700 a includes a plurality ofconcentric regions including a center region 712, a middle-inner region714, a middle region 716, a middle-outer region 718, and an outer region720. Each region is divided into a plurality of segments or pixels thatare each subject to independent heat control using the heat controldevices described herein. The surface 700 a includes thirty-twosegments.

FIG. 7C depicts a schematic view of another implementation of a surface700 c that may be subject to temperature control using the heat controldevices according to one or more implementations of the presentdisclosure. The surface 700 c is divided into a plurality of pixels orhexagonal segment(s) 730. Each pixel or hexagonal segment 730 is subjectto independent heat control using the heat control devices describedherein.

FIG. 7D depicts a schematic view of another implementation of a surface700 c that may be subject to temperature control using the heat controldevices according to one or more implementations of the presentdisclosure. The surface 700 d is divided into a plurality of segments orpixels 740 in an X-Y pattern. Each segment or pixel 740 is subject toindependent heat control using the heat control devices describedherein.

FIG. 8 is a process flow diagram of one implementation of a method 800for in-situ temperature control in accordance with one or moreimplementations of the present disclosure. In some implementations, themethod 800 is performed in a processing system, for example, processingsystem 100 depicted in FIG. 1. The method 800 can be performed in othersystems that benefit from improved temperature control. The method 800may be performed while processing a batch of wafers. For example, ifrunning a batch of 500 wafers, the temperature-sensing disc can besubstituted for a wafer after any number of wafers as chosen by theuser.

At operation 810, a temperature-sensing disc is transferred into aprocessing chamber. In some implementations, the temperature-sensingdisc is delivered into a processing region of the processing chamberwithout breaking vacuum. The temperature-sensing disc may betemperature-sensing disc 300 having cameras 310 configured to performIR-based imaging of the surfaces within the processing chamber. Thesurfaces to be imaged include any surface where temperature control isdesirable. The surfaces to be imaged typically include at least one ofthe surface of the showerhead assembly, the walls of the chamber (e.g.,inner surfaces of the processing chamber including the sidewalls, bottomwall, and ceiling), and the exposed surfaces of the substrate supportassembly (e.g., electrostatic chuck). In some implementations, atemperature of at least one region of at least one chamber surface inthe processing region of the processing chamber is measured by imagingthe at least one surface using the temperature-sensing disc. Forexample, referring to FIG. 2, the cameras 310 on the front surface 320can image the surface of the showerhead assembly 260 and the sidewall234 while the cameras 310 on the back surface 330 can image the surfaceof the electrostatic chuck 242 and the sidewall 234. The infrared imagescaptured by the temperature-sensing disc may be wirelessly transferredto a control system, for example, control system 220.

At operation 820, the captured IR image of the imaged surface isanalyzed to determine whether regions of the imaged surface are within aprocess temperature specification range. The captured IR image may beused to develop a measured temperature profile of the imaged surface.The measured temperature profile may be compared with the temperaturespecification range. The process temperature specification range may beestablished based on desirable temperature ranges for previously runprocesses that achieved desirable results. If the temperature profileindicates that all regions of the surface are within the desiredtemperature range, at operation 830, method 800 ends and substrateprocessing within the chamber continues.

If the measured temperature profile indicates that one or more regionsof the surface are outside of the desired temperature range, atoperation 840, method 800 proceeds to operation 850 and temperaturetuning of the imaged surface is performed. If the measured temperaturefor a specific region is below the desired temperature range, the regionis identified as a cold spot. If the measured temperature is above thedesired temperature range for a specific region, the region isidentified as a hot spot.

At operation 860, the measured temperature profile is compared to abaseline temperature profile, which is determined based on the desiredprocessing temperatures. In some implementations, the baselinetemperature profile is included in a lookup table or other algorithmicapproach. The lookup table may be stored in the control system 220. Themeasured temperature profile is compared with the baseline temperatureprofile to develop a temperature profile map. The temperature controlmap identifies regions that have local cold spots and/or hot spots.

At operation 870, based on the temperature control map, individualthermoelectric modules may be activated to either increase or decreasethe temperature for each region that has been identified as either acold spot or a hot spot. For example, additional voltage may be appliedto a thermoelectric module 464 to increase the pumping of heat.Depending on the location of hot or cold spots as indicated by thetemperature map, the temperature of the electrode and chamber surfacescan be tuned (increased or decreased) at the pixel level to create amore uniform temperature profile.

After the temperature of the imaged surface is brought within thedesired temperature specification, substrate processing may continue.

In summary, some of the benefits of the present disclosure includeapparatus and methods for in-situ temperature measurement for the insideof a processing chamber without venting the processing chamber. Some ofthe implementations described herein provide the ability to measure andadjust temperature levels at the pixel level to create a more uniformtemperature profile. This more uniform temperature profile reduces thepresence of hot spots and cold spots on chamber surfaces, whichsubsequently reduces polymer adhesion on the cold spots, thusmaintaining etch rates and reducing profile control issues. Further,some of the implementations described herein can be performed usingcurrently available hardware and system architecture.

When introducing elements of the present disclosure or exemplary aspectsor implementation(s) thereof, the articles “a,” “an,” “the” and “said”are intended to mean that there are one or more of the elements.

The terms “comprising,” “including” and “having” are intended to beinclusive and mean that there may be additional elements other than thelisted elements.

While the foregoing is directed to implementations of the presentdisclosure, other and further implementations of the disclosure may bedevised without departing from the basic scope thereof, and the scopethereof is determined by the claims that follow.

1. A showerhead assembly, comprising: a first electrode having aplurality of openings therethrough; a gas distribution faceplateattached to a first lower major surface of the first electrode, whereinthe gas distribution plate includes a plurality of through-holes fordelivering process gases to a processing chamber and is divided into aplurality of temperature-control regions; a chill plate positioned abovethe first electrode for providing temperature control; and a pluralityof heat control devices to manage heat transfer within the showerheadassembly, comprising: a thermoelectric module; and a heat pipe assemblycoupled with the thermoelectric module, wherein each of the plurality ofheat control devices is associated with a temperature control region andprovides independent temperature control to its associated temperaturecontrol region.
 2. The showerhead assembly of claim 1, furthercomprising a second electrode positioned between the chill plate and thefirst electrode.
 3. The showerhead assembly of claim 2, wherein thesecond electrode has a first plurality of through-holes each foraccommodating a portion of a heat pipe assembly of the heat controldevice.
 4. The showerhead assembly of claim 3, wherein the secondelectrode has a second plurality of through-holes for delivering processgases into the processing chamber.
 5. The showerhead assembly of claim3, wherein the first electrode has a plurality of holes each foraccommodating a portion of a heat pipe assembly of the heat controldevice.
 6. The showerhead assembly of claim 5, wherein the firstelectrode further has a second plurality of holes for delivering processgases into the processing chamber.
 7. The showerhead assembly of claim3, wherein the thermoelectric module comprises: a heat sink plate; afirst conductive layer; an n-type thermoelectric material; a p-typethermoelectric material; a second conductive layer; and a cooling plate.8. The showerhead assembly of claim 7, wherein the heat sink plate ispositioned adjacent to the chill plate and releases heat into the chillplate and the cooling plate is positioned adjacent to the heat pipeassembly.
 9. A processing chamber, comprising: a chamber body having atop wall, sidewall, and bottom wall defining a processing volume; asubstrate support assembly positioned in the processing volume; and ashowerhead assembly positioned opposite the substrate support assembly,comprising: a first electrode having a plurality of openingstherethrough; a gas distribution faceplate attached to a first lowermajor surface of the electrode, wherein the gas distribution plateincludes a plurality of through-holes for delivering process gases tothe processing volume and is divided into a plurality oftemperature-control regions; a chill plate positioned above the firstelectrode for providing temperature control; and a plurality of heatcontrol devices to manage heat transfer within the showerhead assembly,comprising: a thermoelectric module; and a heat pipe assembly coupledwith the thermoelectric module, wherein each of the plurality of heatcontrol devices is associated with a temperature control region andprovides independent temperature control to its associated temperaturecontrol region.
 10. The processing chamber of claim 9, furthercomprising a second electrode positioned between the chill plate and thefirst electrode.
 11. The processing chamber of claim 10, wherein thesecond electrode has: a first plurality of through-holes each foraccommodating a portion of a heat pipe assembly of the heat controldevice; and a second plurality of through-holes for delivering processgases into the processing volume.
 12. The processing chamber of claim 9,wherein the first electrode has: a plurality of holes each foraccommodating a portion of a heat pipe assembly of the heat controldevice; and a plurality of through-holes for delivering process gasesinto the processing volume.
 13. The processing chamber of claim 9,wherein the thermoelectric module comprises: a heat sink plate; a firstconductive layer; an n-type thermoelectric material; a p-typethermoelectric material; a second conductive layer; and a cooling plate.14. The processing chamber of claim 13, wherein the heat sink plate ispositioned adjacent to the chill plate and releases heat into the chillplate and the cooling plate is positioned adjacent to the heat pipeassembly.
 15. The processing chamber of claim 9, further comprising atemperature-sensing disc positioned in the processing volume andcomprising: a disc-shaped body having: a diameter of 300 millimeters; afront surface; a back surface opposing the front surface; one or morecameras positioned on at least one of the front surface and the backsurface, wherein the one or more cameras are configured to performIR-based imaging.
 16. A method, comprising: delivering atemperature-sensing disc into a processing region of a processingchamber without breaking vacuum, wherein the temperature-sensing discincludes one or more cameras configured to perform IR-based imaging;measuring a temperature of at least one region of at least one chambersurface in the processing region of the processing chamber by imagingthe at least one surface using the temperature-sensing disc; comparingthe measured temperature to a desired temperature to determine atemperature difference; and adjusting a temperature of the at least onechamber surface to compensate for the temperature difference.
 17. Themethod of claim 16, wherein the at least one chamber surface is selectedfrom a surface of a showerhead assembly, a wall of the processingchamber, and a surface of the substrate support assembly.
 18. The methodof claim 17, wherein one or more cameras on a front surface of thetemperature-sensing disc image the surface of the showerhead assemblyand one or more cameras on a back surface of the temperature-sensingdisc image a surface of the substrate support assembly.
 19. The methodof claim 16, wherein comparing the measured temperature to a desiredtemperature further comprises: identifying the at least one region as acold spot if the measured temperature is below the desired temperaturerange; and identifying the at least one region as a hot spot if themeasured temperature is above the desired temperature range.
 20. Themethod of claim 16, wherein adjusting a temperature of the at least onechamber surface to compensate for the temperature difference comprisesactivating a thermoelectric module associated with a region to eitherincrease or decrease the temperature for each region that has beenidentified as either a cold spot or a hot spot.